The present invention relates to a method and means for engaging elevator car and landing doors.
In a typical elevator or lift installation, the vertically moving elevator car is positioned so as to align its entrance with corresponding openings at a plurality of landings in a multi-floor building. Modern installations typically have one or more horizontally sliding doors disposal on the elevator car and one set disposed on each of the landing floors, all of which remain closed during vertical movement of the elevator.
Upon arrival of the elevator car at a floor or landing to be serviced, a door opening mechanism is activated which drives the elevator car doors horizontally for permitting access to the elevator car. In typical installations today, one or more vanes, projecting from the surface of the elevator car door in the direction of the adjacent landing door, engage various structures, such as vanes, rollers or other protrusions projecting from the landing door, for also driving the landing door horizontally, thereby permitting passengers to traverse between the car and the serviced landing.
Code developments have long required the landing doors to remain fastened securely against unauthorized entry unless an elevator car is positioned so as to correspond with the landing. Likewise, recent code developments in certain countries have required that the elevator car door remain latched against manual movement unless the car is positioned so as to register with a landing. Various mechanisms and systems have been proposed in the prior art to secure and unsecure landing and elevator car doors as the elevator car traverses the elevator hoistway. Various mechanical and electrical interlock systems used to date have the disadvantage of being complex, and subject to malfunction and/or frequent service requirements. As will be appreciated by those skilled in the art, failure or malfunction may lead to the potential for a code violation or, even more seriously, shut down of the operation of the elevator or entrapment of the passenger.
What is needed is a simple, effective mechanical system for appropriately engaging the elevator landing doors and elevator car doors at a serviced landing, while securing the elevator car doors against inappropriate opening when the elevator car is not correctly positioned within the hoistway.
It is therefor an object of the present invention to provide a simple mechanical system for engaging the elevator car door and landing doors when the elevator is positioned at one of the landings, and, additionally, for securing the elevator doors when the elevator is intermediate the landings.
According to the present invention, a mechanical door coupling is provided on the exterior surface of an elevator door. The coupling includes a first fixed vane extending longitudinally vertically, is fixed to the elevator door and horizontally movable therewith. The coupling according to the present invention also includes a second vane, mounted to the door by a pair of parallel pivoted links. The second movable vane is arranged adjacent the first vane and parallel thereto, and includes a deterrent hook member disposed at one end thereof. The second vane is positioned by an engagement link, pivotally secured to the second vane and including an engagement roller contacting to a camway fixed to the elevator car. The engagement link includes an engagement hook, which engages an engagement striker when the elevator door and corresponding hallway door are in full engagement.
In operation, the coupling according to the present invention maintains the fixed and second vanes spaced apart when the elevator car doors are fully closed to permit the vanes and elevator to easily pass the landing door rollers during movement of the elevator car. When the car is positioned in registration with a landing, the initial opening movement of the elevator door traps the landing door rollers between vanes, maintaining the vanes at a fixed horizontal distance and causing the engagement hook to engage the engagement striker, thereby securely trapping the landing door rollers and locking the elevator and landing doors laterally for sliding operation.
During periods in which the elevator is between landings, the system according to the present invention acts as an evacuation deterrent in the event a passenger attempts to slide the elevator door open. The movement of the door, combined with the action of the engagement link roller and camway cause the second vane to move closer to the first vane, in turn causing the deterrent hook secured to the second vane to engage the deterrent striker secured to the elevator car. The engagement of these two elements blocks the elevator door from further motion in the horizontally opened direction.